The ugliest global-warming chart you’ll ever need to see

Analysis As you’ve likely read in many a headline-shouting article, our precious Blue Marble Earth just experienced its warmest year since reliable record-keeping began.

It’s getting ugly out there. According to the rapidly advancing field of attribution science, global warming and its evil twin climate change are rapidly exacerbating natural weather cycles. What’s even uglier is the unarguable fact that not only is the globe getting warmer, it’s also getting warmer faster.

How much faster? We’ll get to that.

The essential reasoning of attribution science is easy to explain. Take the recent Los Angeles fires, for example, which suffered from the climate-change–magnified extreme wet-dry seesaw of southern US weather. First, unusually high precipitation for a couple of seasons resulted in more vegetation. Then that drenching was followed by unusually dry weather that sucked all the moisture out said vegetation. One spark on a day bedeviled by powerful hot, dry Santa Ana winds and — poof! — wildfires exploded into urban conflagrations.

Did climate change amplify the Santa Ana winds that drove the LA fires? That jury is still out. But did a climate-change-worsened hot-and-rain-less autumn dry out vegetation overgrown from climate-change–magnified precipitation in previous years? Most definitely.

Increasing global temperatures have also made life ugly for the victims of Hurricanes Ida and Helene in America, Typhoon Gaemi in the Philippines, and a series of massive floods in South Asia. In each of these cases, climate change aggravated matters: Warmer air carries more moisture. Warmer oceans provide increased energy to storms, such as hurricanes and typhoons. There may not be more cyclonic storms, but the ones that do occur in a warming world are more powerful, faster-growing, and wetter.

The Earth is heating up. No argument. That heat is exacerbating extreme weather. No argument. The effects of climate change are no longer a worry for the future — the era that some wordsmiths have dubbed the “climate crisis” is upon us now. And its driver, global warming, is growing at an increasing pace.

To understand just how much and how fast that pace is increasing, we turn to another ugliness: Data analysis — specifically, visualizations of large data sets such as the one used to create the chart below, which crams 1,460 data points into a month-by-month representation of how the Earth, both on land and on the surface of the sea, have warmed since reasonably accurate global measurements began to become available in 1880.

Monthly global temperatures since 1880 … Sometimes a simple story takes 1,460 data points to tell. Click for full resolution

This chart is an ugly pile-o-data, isn’t it? And no, we don’t just mean the chart’s impenetrable tangle of squiggles. We also mean what those squiggly lines represent: A speedily warming globe, over the past century or so, at least.

But before we analyze this chart’s warnings, a bit of explanation about what its colorful squiggles represent:

• Each wavy horizontal line tracks one year’s month-by-month global temperature.
• Each decade is identified by its own color.
• The first year of each decade is identified on the left.
• Each decade’s first-year line is thicker and in the same color as its decade’s other lines.
• 2024 is given its own slightly chubbier line.

Following so far? Great — but now things get a bit more complicated.

On the right of the chart you’ll see a rising series of temperatures, from -0.25°C (-0.45°F) up to 1°C (1.8°F). Those are the y-axis values for each of the 1,460 temperature-measurement data points that create the chart. They indicate the degree (pun intended) of variance for each measurement from the average of global temperatures from 1951 to 1980.

The sharp-eyed Reg reader will notice that the temperatures in this chart don’t pass the 1.5°C (2.7°F) threshold outlined in the Paris Agreement as the rise to be avoided if at all possible. (Spoiler alert: It’s not possible.) That’s the temperature barrier upon which those aforementioned headline-shouting popular-press articles are based.

The reason for that discrepancy is simple: Different climate analysts use different baselines for calculating global temperature rise. The US government’s National Oceanic and Atmospheric Administration, aka NOAA, for example, uses a broad baseline it defines generally as the “pre-industrial period”, which they peg as being from 1850 through 1900. If you use NOAA’s baseline, then, yes, 2024 popped above that 1.5°C threshold.

NOAA is, incidentally, facing staffing cuts as part of the White House’s sweeping layoffs and upheaval across the federal government.

This data from which this chart is built uses a more conservative dataset, one that doesn’t begin in 1850. It’s instead built using data from a set of measurements that begin in 1880, not 1850 — and even beginning three decades later than NOAA’s dataset, it took even more decades for reliable data to fully stabilize enough to settle on a more conservatively accurate baseline.

But — for Svante Arrhenius’ sake — don’t get caught up in some pointless argument as to which baseline is more reliable or whether those “we’ve passed 1.5°C!” headlines are or are not accurate. No matter what baseline you choose, it’s unarguable that the Earth is now rapidly heating.

Just look at our at-first-impenetrable chart. As you can see, temperature readings from 1900 and earlier — excepting the somewhat questionable readings from the 1880s — don’t fully stabilize until about mid-century, when temperature measurements settle around the 0°C variance matching the 1951-1980 baseline.

But look above that spaghettified morass of squiggly lines clustered around the bottom third of the chart, and notice that although at first rising incrementally, temperatures were not chart-busters until 1970, when, as the old saying goes, “Katy, bar the door!”

From 1970 until today, the Earth’s temperature has been reliably recorded to be rising quite quickly, leaving the relatively slow increases of the decades from 1880 though 1960. (The year 2000 may at first seem an anomaly, but although that year began with an unusually cool January, it then joined its rightful place in the ongoing progression upwards.)

What’s more, temperature increases are accelerating. Notice how much more breathing room there is between the horizontal wiggles beginning around 1970, and how that white space grows as the years pass.

The Earth is getting hotter, and it’s getting hotter faster. This ugly reality is readily apparent when looking at this ugly chart — a chart that’s a conservatively compiled visual representation of rapidly increasing global warming based on objective, internationally obtained data that has been well-vetted and carefully tuned to account for observational anomalies and measurement-method distortions.

We can now finally and definitively provide a data-supported answer to that ancient pickup line, “Is it hot in here? Or is it just you?” The unarguable answer: It is indeed hot in here. Dangerously hot. And the acceleration of that heating is increasing. ®

Frequently Anticipated Question

Q. But Rik, if you zoom out of the graph to view the lines over centuries, doesn’t the Earth go through these ups and downs all the time? Why worry so much about one blip right now?

A. In the past, we have indeed run through multi-degree changes, but they have taken tens to hundreds of thousands of years* to cycle from one extreme to another. What we’re experiencing now is a gobsmackingly meteoric rise in temperatures, one so fast that living organisms — such as you and I — will not have nearly enough time to adapt, let alone evolve.

* That is, of course, if you believe that the Earth is more than 6,000 years old.